How to pass json string to webmethod c# ASP.NET

Im trying to stringify a javascript object and then pass the string as a parameter to a WebMethod in Code Behind. I can’t get it to work as I get a Internal Server Error of 500 and the stacktrace says that value is missing for parameter.

Here is the javascript code:

var jSon = JSON.stringify(javascriptObject); 
// "{"Foretagsnamn":"Avector","BGFarg":"000000","TextColor":"fafafa","FooterFarg":"ffffff","FooterColor":"000000","FooterLinkColor":"050505","FeaturedBorderColor":"","HoverFarg":"12ebeb","RutFarg":"0d0d0d","SelectedRutFarg":"","RutColor":"FFFFFF","LankColor":"","DelaMedSig":"1","PersonalSida":"0","StartpageTitle":"","StartpageDescription":"","GoogleMaps":"<iframe width="425" height="350" frameborder="0" scrolling="no" marginheight="0" marginwidth="0" src="https://maps.google.se/maps?f=q&amp;source=embed&amp;hl=sv&amp;geocode=&amp;q=Avector AB&amp;aq=&amp;sll=56.225986,12.870827&amp;sspn=0.076248,0.154324&amp;ie=UTF8&amp;hq=Avector AB&amp;hnear=&amp;t=m&amp;cid=645910733081021950&amp;iwloc=A&amp;ll=56.224594,12.859229&amp;spn=0,0&amp;output=embed"></iframe><br /><small><a href="https://maps.google.se/maps?f=q&amp;source=embed&amp;hl=sv&amp;geocode=&amp;q=Avector AB&amp;aq=&amp;sll=56.225986,12.870827&amp;sspn=0.076248,0.154324&amp;ie=UTF8&amp;hq=Avector AB&amp;hnear=&amp;t=m&amp;cid=645910733081021950&amp;iwloc=A&amp;ll=56.224594,12.859229&amp;spn=0,0" style="text-align:left">Visa större karta</a></small>","HittaKartaUrl":"http://www.hitta.se/avector ab/ängelholm/hxTP-4v1HG?vad=Avector AB","EniroKartaUrl":"http://kartor.eniro.se/m/aKkhi","Ikoner":"2","Email":"<a href="https://getridbug.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="224b4c444d6243544741564d500c414d4f">[email protected]</a>","AdressSida":"1","shadowColor":"ffffff","lineColor":"2b292b","MenuHoverIcon":"Välj bild från server","fontFamily":"Verdana","supportText":"Support Avector","captcha":true,"metaKeywords":"","ShowSupportInFooter":true}"

$.ajax({
    type: "POST",
    url: "Post/Installningar.aspx/Updatera",
    data: jSon,
    contentType: "application/json; charset=utf-8",
    dataType: "json",
    success: function (result) {

        var resultAsString = result.d;
        //_this.parent().siblings('.SavedStatus').html(resultAsString);

        if (resultAsString == "1") { // Gick bra att spara.
           alert("Uppgifterna är sparade.");
           document.location = document.location;
        }
        else {
           $('#StatusText').html("Gick inte att spara uppgifterna.");
        }


    },
    error: function (xhr, ajaxOptions, thrownError) {

    }
});

And here Is the webmethod:

[WebMethod]
public static string Updatera(string jSon)
{

It feels like I’ve tried everything that I’ve found when searching by google and here on SO.

I’ve also tried this guide that many refer to: http://encosia.com/using-jquery-to-directly-call-aspnet-ajax-page-methods/

Any ideas?

Answers:

Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

First, you need to use:

var jSon = JSON.stringify({obj:javascriptObject});

instead of:

var jSon = JSON.stringify(javascriptObject);

Then your WebMethod would be like:

[WebMethod]
public static string Updatera(aData obj)
{
    // logic code 
}

Now here aData is your class something like below :

public class aData { 
    public string Foretagsnamn  { get; set; }
    public string BGFarg  { get; set; }
    public string TextColor  { get; set; }
    public string FooterFarg  { get; set; }
    public string Email  { get; set; }
}

So your final code look like
jQuery:

var jSon = JSON.stringify({ obj:javascriptObject });
$.ajax({
    type: "POST",
    url: "Post/Installningar.aspx/Updatera",
    data: jsonData,
    contentType: "application/json; charset=utf-8",
    dataType: "json",
    success: OnSuccess,
    error: OnErrorCall
});

function OnSuccess(response){
    // Do something
}
function OnErrorCall(){
    // Do something
}

Code Behind:

public class aData { 
    public string Foretagsnamn { get; set; }
    public string BGFarg { get; set; }
    public string TextColor { get; set; }
    public string FooterFarg { get; set; }
    public string Email { get; set; }
}


[WebMethod]
public static string Updatera(aData obj)
{
    // Logic code
}

Method 2

Use this format for ajax post format :

var jSon = JSON.stringify(javascriptObject);

Your Json Format will be like this :
‘{name: “‘ + name +’” }’,

function ShowCurrentTime() {
    $.ajax({
        type: "POST",
        url: "Installningar.aspx/Updatera",
        data: jSon; 
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: OnSuccess,
        failure: function(response) {
            alert(response.d);
        }
    });
}
function OnSuccess(response) {
    alert(response.d);
}

Follow this step for complete run your code :
http://www.aspsnippets.com/Articles/Calling-ASPNet-WebMethod-using-jQuery-AJAX.aspx

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0